Predicting the clinical behavior and trajectory of chromophobe renal cell carcinoma (ChRCC) by histologic features has so far proven to be challenging. It is known that ChRCC represents a heterogeneous group of neoplasms demonstrating variable, yet distinctive morphologic and genetic profiles. In this international multi-institutional study, we aimed to assess the impact of histologic diversity in ChRCC (classic/eosinophilic versus rare subtypes) on survival outcome. This is an international multi-institutional matched case-control study including 14 institutions, examining the impact of histologic subtypes of ChRCC on survival outcome. The study group (cases) included 89 rare subtypes of ChRCC. The control group consisted of 70 cases of ChRCC including classic and eosinophilic features, age- and tumor size-matched. Most of the rare subtypes were adenomatoid cystic/pigmented ChRCC (66/89, 74.2%), followed by multicystic ChRCC (10/89, 11.2%), and papillary ChRCC (9/89, 10.1%). In the control group, there were 62 (88.6%) classic and 8 (11.4%) eosinophilic ChRCC. There were no statistically significant differences between the study and control groups for age at diagnosis, gender distribution, tumor size, presence of tumor necrosis, presence of sarcomatoid differentiation, and adverse outcomes. No statistically significant differences were found in clinical outcome between the rare subtypes and classic/eosinophilic groups by tumor size, necrosis, and sarcomatoid differentiation. Further, no statistically significant differences were found in clinical outcome between the two groups, stratified by tumor size, necrosis, and sarcomatoid differentiation. Our findings corroborated previous studies that both sarcomatoid differentiation and tumor necrosis were significantly associated with poor clinical outcome in classic/eosinophilic ChRCC, and this was proven to be true for ChRCC with rare histologic subtypes as well. This study suggests that rare morphologic patterns in ChRCC without other aggressive features play no role in determining the clinical behavior of the tumor.
Annals of diagnostic pathology. 2022 May 20 [Epub ahead of print]
Jiri Kolar, Andrea Feu Llaurado, Monika Ulamec, Faruk Skenderi, Delia Perez-Montiel, Isabel Alvarado-Cabrero, Stela Bulimbasic, Maris Sperga, Maria Tretiakova, Adeboye O Osunkoya, Joanna Rogala, Eva Comperat, Viliam Gal, Ana Dunatov, Kristyna Pivovarcikova, Kvetoslava Michalova, Adriena Bartos Vesela, Maryna Slisarenko, Andrea Peterikova Strakova, Tomas Pitra, Milan Hora, Michal Michal, Reza Alaghehbandan, Ondrej Hes
Department of Urology, Charles University, Faculty of Medicine and University Hospital in Plzen, Plzen, Czech Republic., Department of Pathology, Bellvitge Hospital, Barcelona, Spain., Department of Pathology, Sestre milosrdnice University Hospital Center, Department of Pathology and Scientific Centre of Excellence for Reproductive and Regenerative Medicine, School of Medicine, University of Zagreb, Croatia., Department of Pathology, University of Sarajevo, Faculty of Health Sciences, Sarajevo, Bosnia and Herzegovina., Department of Pathology, Institute Nacional de Cancerologia, Mexico City, Mexico., Department of Pathology, Centro Medico, Mexico City, Mexico., Department of Pathology, University Hospital Zagreb, Croatia., Department of Pathology, Stradin's University, Riga, Latvia., Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA., Departments of Pathology and Urology, Emory University School of Medicine, Atlanta, GA, USA., Department of Pathology, Charles University, Faculty of Medicine and University Hospital in Plzen, Plzen, Czech Republic., Department of Pathology, University of Vienna, Vienna, Austria., Department of Pathology, Alpha Medical Pathologia, Bratislava, Slovakia., Department of Pathology, University of Split, Croatia., Department of Pathology, Faculty of Medicine, University of British Columbia, Royal Columbian Hospital, Vancouver, BC, Canada., Department of Pathology, Charles University, Faculty of Medicine and University Hospital in Plzen, Plzen, Czech Republic. Electronic address: .